/*
 * scsinvme.cpp
 *
 * Home page of code is: https://www.smartmontools.org
 *
 * Copyright (C) 2020-21 Christian Franke
 * Copyright (C) 2018 Harry Mallon <hjmallon@gmail.com>
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

#include "dev_interface.h"
#include "dev_tunnelled.h"
#include "nvmecmds.h"
#include "scsicmds.h"
#include "sg_unaligned.h"
#include "utility.h"

#include <errno.h>

const char *scsinvme_cpp_svnid = "$Id: scsinvme.cpp 5337 2022-02-27 07:53:55Z dpgilbert $";

// SNT (SCSI NVMe Translation) namespace and prefix
namespace snt
{

  /////////////////////////////////////////////////////////////////////////////
  // sntasmedia_device

  class sntasmedia_device
      : public tunnelled_device<
            /*implements*/ nvme_device,
            /*by tunnelling through a*/ scsi_device>
  {
  public:
    sntasmedia_device(smart_interface *intf, scsi_device *scsidev,
                      const char *req_type, unsigned nsid);

    virtual ~sntasmedia_device();

    virtual bool nvme_pass_through(const nvme_cmd_in &in, nvme_cmd_out &out) override;
  };

  sntasmedia_device::sntasmedia_device(smart_interface *intf, scsi_device *scsidev,
                                       const char *req_type, unsigned nsid)
      : smart_device(intf, scsidev->get_dev_name(), "sntasmedia", req_type),
        tunnelled_device<nvme_device, scsi_device>(scsidev, nsid)
  {
    set_info().info_name = strprintf("%s [USB NVMe ASMedia]", scsidev->get_info_name());
  }

  sntasmedia_device::~sntasmedia_device()
  {
  }

  bool sntasmedia_device::nvme_pass_through(const nvme_cmd_in &in, nvme_cmd_out & /* out */)
  {
    unsigned size = in.size;
    unsigned cdw10_hi = in.cdw10 >> 16;
    switch (in.opcode)
    {
    case smartmontools::nvme_admin_identify:
      if (in.cdw10 == 0x0000001) // Identify controller
        break;
      if (in.cdw10 == 0x0000000)
      { // Identify namespace
        if (in.nsid == 1)
          break;
        return set_err(ENOSYS, "NVMe Identify Namespace 0x%x not supported", in.nsid);
      }
      return set_err(ENOSYS, "NVMe Identify with CDW10=0x%08x not supported", in.cdw10);
    case smartmontools::nvme_admin_get_log_page:
      if (!(in.nsid == 0xffffffff || !in.nsid))
        return set_err(ENOSYS, "NVMe Get Log Page with NSID=0x%x not supported", in.nsid);
      if (size > 0x200)
      { // Reading more results in command timeout
        // TODO: Add ability to return short reads to caller
        size = 0x200;
        cdw10_hi = (size / 4) - 1;
        pout("Warning: NVMe Get Log truncated to 0x%03x bytes, 0x%03x bytes zero filled\n", size, in.size - size);
      }
      break;
    default:
      return set_err(ENOSYS, "NVMe admin command 0x%02x not supported", in.opcode);
      break;
    }
    if (in.cdw11 || in.cdw12 || in.cdw13 || in.cdw14 || in.cdw15)
      return set_err(ENOSYS, "Nonzero NVMe command dwords 11-15 not supported");

    uint8_t cdb[16] = {
        0,
    };
    cdb[0] = 0xe6;
    cdb[1] = in.opcode;
    // cdb[2] = ?
    cdb[3] = (uint8_t)in.cdw10;
    // cdb[4..6] = ?
    cdb[7] = (uint8_t)cdw10_hi;
    // cdb[8..15] = ?

    scsi_cmnd_io io_hdr = {};
    io_hdr.cmnd = cdb;
    io_hdr.cmnd_len = sizeof(cdb);
    io_hdr.dxfer_dir = DXFER_FROM_DEVICE;
    io_hdr.dxferp = (uint8_t *)in.buffer;
    io_hdr.dxfer_len = size;
    memset(in.buffer, 0, in.size);

    scsi_device *scsidev = get_tunnel_dev();
    if (!scsidev->scsi_pass_through_and_check(&io_hdr, "sntasmedia_device::nvme_pass_through: "))
      return set_err(scsidev->get_err());

    // out.result = ?;
    return true;
  }

  /////////////////////////////////////////////////////////////////////////////
  // sntjmicron_device

#define SNT_JMICRON_NVME_SIGNATURE 0x454d564eu // 'NVME' reversed (little endian)
#define SNT_JMICRON_CDB_LEN 12
#define SNT_JMICRON_NVM_CMD_LEN 512

  class sntjmicron_device
      : public tunnelled_device<
            /*implements*/ nvme_device,
            /*by tunnelling through a*/ scsi_device>
  {
  public:
    sntjmicron_device(smart_interface *intf, scsi_device *scsidev,
                      const char *req_type, unsigned nsid);

    virtual ~sntjmicron_device();

    virtual bool open() override;

    virtual bool nvme_pass_through(const nvme_cmd_in &in, nvme_cmd_out &out) override;

  private:
    enum
    {
      proto_nvm_cmd = 0x0,
      proto_non_data = 0x1,
      proto_dma_in = 0x2,
      proto_dma_out = 0x3,
      proto_response = 0xF
    };
  };

  sntjmicron_device::sntjmicron_device(smart_interface *intf, scsi_device *scsidev,
                                       const char *req_type, unsigned nsid)
      : smart_device(intf, scsidev->get_dev_name(), "sntjmicron", req_type),
        tunnelled_device<nvme_device, scsi_device>(scsidev, nsid)
  {
    set_info().info_name = strprintf("%s [USB NVMe JMicron]", scsidev->get_info_name());
  }

  sntjmicron_device::~sntjmicron_device()
  {
  }

  bool sntjmicron_device::open()
  {
    // Open USB first
    if (!tunnelled_device<nvme_device, scsi_device>::open())
      return false;

    // No sure how multiple namespaces come up on device so we
    // cannot detect e.g. /dev/sdX is NSID 2.
    // Set to broadcast if not available
    if (!get_nsid())
    {
      set_nsid(0xFFFFFFFF);
    }

    return true;
  }

  // cdb[0]: ATA PASS THROUGH (12) SCSI command opcode byte (0xa1)
  // cdb[1]: [ is admin cmd: 1 ] [ protocol : 7 ]
  // cdb[2]: reserved
  // cdb[3]: parameter list length (23:16)
  // cdb[4]: parameter list length (15:08)
  // cdb[5]: parameter list length (07:00)
  // cdb[6]: reserved
  // cdb[7]: reserved
  // cdb[8]: reserved
  // cdb[9]: reserved
  // cdb[10]: reserved
  // cdb[11]: CONTROL (?)
  bool sntjmicron_device::nvme_pass_through(const nvme_cmd_in &in, nvme_cmd_out &out)
  {
    /* Only admin commands used */
    constexpr bool admin = true;

    // 1: "NVM Command Set Payload"
    {
      unsigned char cdb[SNT_JMICRON_CDB_LEN] = {0};
      cdb[0] = SAT_ATA_PASSTHROUGH_12;
      cdb[1] = (admin ? 0x80 : 0x00) | proto_nvm_cmd;
      sg_put_unaligned_be24(SNT_JMICRON_NVM_CMD_LEN, &cdb[3]);

      unsigned nvm_cmd[SNT_JMICRON_NVM_CMD_LEN / sizeof(unsigned)] = {0};
      nvm_cmd[0] = SNT_JMICRON_NVME_SIGNATURE;
      // nvm_cmd[1]: reserved
      nvm_cmd[2] = in.opcode; // More of CDW0 may go in here in future
      nvm_cmd[3] = in.nsid;
      // nvm_cmd[4-5]: reserved
      // nvm_cmd[6-7]: metadata pointer
      // nvm_cmd[8-11]: data ptr (?)
      nvm_cmd[12] = in.cdw10;
      nvm_cmd[13] = in.cdw11;
      nvm_cmd[14] = in.cdw12;
      nvm_cmd[15] = in.cdw13;
      nvm_cmd[16] = in.cdw14;
      nvm_cmd[17] = in.cdw15;
      // nvm_cmd[18-127]: reserved

      if (isbigendian())
        for (unsigned i = 0; i < (SNT_JMICRON_NVM_CMD_LEN / sizeof(uint32_t)); i++)
          swapx(&nvm_cmd[i]);

      scsi_cmnd_io io_nvm = {};

      io_nvm.cmnd = cdb;
      io_nvm.cmnd_len = SNT_JMICRON_CDB_LEN;
      io_nvm.dxfer_dir = DXFER_TO_DEVICE;
      io_nvm.dxferp = (uint8_t *)nvm_cmd;
      io_nvm.dxfer_len = SNT_JMICRON_NVM_CMD_LEN;

      scsi_device *scsidev = get_tunnel_dev();
      if (!scsidev->scsi_pass_through_and_check(&io_nvm,
                                                "sntjmicron_device::nvme_pass_through:NVM: "))
        return set_err(scsidev->get_err());
    }

    // 2: DMA or Non-Data
    {
      unsigned char cdb[SNT_JMICRON_CDB_LEN] = {0};
      cdb[0] = SAT_ATA_PASSTHROUGH_12;

      scsi_cmnd_io io_data = {};
      io_data.cmnd = cdb;
      io_data.cmnd_len = SNT_JMICRON_CDB_LEN;

      switch (in.direction())
      {
      case nvme_cmd_in::no_data:
        cdb[1] = (admin ? 0x80 : 0x00) | proto_non_data;
        io_data.dxfer_dir = DXFER_NONE;
        break;
      case nvme_cmd_in::data_out:
        cdb[1] = (admin ? 0x80 : 0x00) | proto_dma_out;
        sg_put_unaligned_be24(in.size, &cdb[3]);
        io_data.dxfer_dir = DXFER_TO_DEVICE;
        io_data.dxferp = (uint8_t *)in.buffer;
        io_data.dxfer_len = in.size;
        break;
      case nvme_cmd_in::data_in:
        cdb[1] = (admin ? 0x80 : 0x00) | proto_dma_in;
        sg_put_unaligned_be24(in.size, &cdb[3]);
        io_data.dxfer_dir = DXFER_FROM_DEVICE;
        io_data.dxferp = (uint8_t *)in.buffer;
        io_data.dxfer_len = in.size;
        memset(in.buffer, 0, in.size);
        break;
      case nvme_cmd_in::data_io:
      default:
        return set_err(EINVAL);
      }

      scsi_device *scsidev = get_tunnel_dev();
      if (!scsidev->scsi_pass_through_and_check(&io_data,
                                                "sntjmicron_device::nvme_pass_through:Data: "))
        return set_err(scsidev->get_err());
    }

    // 3: "Return Response Information"
    {
      unsigned char cdb[SNT_JMICRON_CDB_LEN] = {0};
      cdb[0] = SAT_ATA_PASSTHROUGH_12;
      cdb[1] = (admin ? 0x80 : 0x00) | proto_response;
      sg_put_unaligned_be24(SNT_JMICRON_NVM_CMD_LEN, &cdb[3]);

      unsigned nvm_reply[SNT_JMICRON_NVM_CMD_LEN / sizeof(unsigned)] = {0};

      scsi_cmnd_io io_reply = {};

      io_reply.cmnd = cdb;
      io_reply.cmnd_len = SNT_JMICRON_CDB_LEN;
      io_reply.dxfer_dir = DXFER_FROM_DEVICE;
      io_reply.dxferp = (uint8_t *)nvm_reply;
      io_reply.dxfer_len = SNT_JMICRON_NVM_CMD_LEN;

      scsi_device *scsidev = get_tunnel_dev();
      if (!scsidev->scsi_pass_through_and_check(&io_reply,
                                                "sntjmicron_device::nvme_pass_through:Reply: "))
        return set_err(scsidev->get_err());

      if (isbigendian())
        for (unsigned i = 0; i < (SNT_JMICRON_NVM_CMD_LEN / sizeof(uint32_t)); i++)
          swapx(&nvm_reply[i]);

      if (nvm_reply[0] != SNT_JMICRON_NVME_SIGNATURE)
        return set_err(EIO, "Out of spec JMicron NVMe reply");

      int status = nvm_reply[5] >> 17;

      if (status > 0)
        return set_nvme_err(out, status);

      out.result = nvm_reply[2];
    }

    return true;
  }

  /////////////////////////////////////////////////////////////////////////////
  // sntrealtek_device

  class sntrealtek_device
      : public tunnelled_device<
            /*implements*/ nvme_device,
            /*by tunnelling through a*/ scsi_device>
  {
  public:
    sntrealtek_device(smart_interface *intf, scsi_device *scsidev,
                      const char *req_type, unsigned nsid);

    virtual ~sntrealtek_device();

    virtual bool nvme_pass_through(const nvme_cmd_in &in, nvme_cmd_out &out) override;
  };

  sntrealtek_device::sntrealtek_device(smart_interface *intf, scsi_device *scsidev,
                                       const char *req_type, unsigned nsid)
      : smart_device(intf, scsidev->get_dev_name(), "sntrealtek", req_type),
        tunnelled_device<nvme_device, scsi_device>(scsidev, nsid)
  {
    set_info().info_name = strprintf("%s [USB NVMe Realtek]", scsidev->get_info_name());
  }

  sntrealtek_device::~sntrealtek_device()
  {
  }

  bool sntrealtek_device::nvme_pass_through(const nvme_cmd_in &in, nvme_cmd_out & /* out */)
  {
    unsigned size = in.size;
    switch (in.opcode)
    {
    case smartmontools::nvme_admin_identify:
      if (in.cdw10 == 0x0000001) // Identify controller
        break;
      if (in.cdw10 == 0x0000000)
      { // Identify namespace
        if (in.nsid == 1)
          break;
        return set_err(ENOSYS, "NVMe Identify Namespace 0x%x not supported", in.nsid);
      }
      return set_err(ENOSYS, "NVMe Identify with CDW10=0x%08x not supported", in.cdw10);
    case smartmontools::nvme_admin_get_log_page:
      if (!(in.nsid == 0xffffffff || !in.nsid))
        return set_err(ENOSYS, "NVMe Get Log Page with NSID=0x%x not supported", in.nsid);
      if (size > 0x200)
      { // Reading more apparently returns old data from previous command
        // TODO: Add ability to return short reads to caller
        size = 0x200;
        pout("Warning: NVMe Get Log truncated to 0x%03x bytes, 0x%03x bytes zero filled\n", size, in.size - size);
      }
      break;
    default:
      return set_err(ENOSYS, "NVMe admin command 0x%02x not supported", in.opcode);
      break;
    }
    if (in.cdw11 || in.cdw12 || in.cdw13 || in.cdw14 || in.cdw15)
      return set_err(ENOSYS, "Nonzero NVMe command dwords 11-15 not supported");

    uint8_t cdb[16] = {
        0,
    };
    cdb[0] = 0xe4;
    sg_put_unaligned_le16(size, cdb + 1);
    cdb[3] = in.opcode;
    cdb[4] = (uint8_t)in.cdw10;

    scsi_cmnd_io io_hdr = {};
    io_hdr.cmnd = cdb;
    io_hdr.cmnd_len = sizeof(cdb);
    io_hdr.dxfer_dir = DXFER_FROM_DEVICE;
    io_hdr.dxferp = (uint8_t *)in.buffer;
    io_hdr.dxfer_len = size;
    memset(in.buffer, 0, in.size);

    scsi_device *scsidev = get_tunnel_dev();
    if (!scsidev->scsi_pass_through_and_check(&io_hdr, "sntrealtek_device::nvme_pass_through: "))
      return set_err(scsidev->get_err());

    // out.result = ?; // TODO
    return true;
  }

} // namespace snt

using namespace snt;

nvme_device *smart_interface::get_snt_device(const char *type, scsi_device *scsidev)
{
  if (!scsidev)
    throw std::logic_error("smart_interface: get_snt_device() called with scsidev=0");

  // Take temporary ownership of 'scsidev' to delete it on error
  scsi_device_auto_ptr scsidev_holder(scsidev);
  nvme_device *sntdev = 0;

  // TODO: Remove this and adjust drivedb entry accordingly when no longer EXPERIMENTAL
  if (!strcmp(type, "sntjmicron#please_try"))
  {
    set_err(EINVAL, "USB to NVMe bridge [please try '-d sntjmicron' and report result to: " PACKAGE_BUGREPORT "]");
    return 0;
  }

  if (!strcmp(type, "sntasmedia"))
  {
    // No namespace supported
    sntdev = new sntasmedia_device(this, scsidev, type, 0xffffffff);
  }

  else if (!strncmp(type, "sntjmicron", 10))
  {
    int n1 = -1, n2 = -1, len = strlen(type);
    unsigned nsid = 0; // invalid namespace id -> use default
    sscanf(type, "sntjmicron%n,0x%x%n", &n1, &nsid, &n2);
    if (!(n1 == len || n2 == len))
    {
      set_err(EINVAL, "Invalid NVMe namespace id in '%s'", type);
      return 0;
    }
    sntdev = new sntjmicron_device(this, scsidev, type, nsid);
  }

  else if (!strcmp(type, "sntrealtek"))
  {
    // No namespace supported
    sntdev = new sntrealtek_device(this, scsidev, type, 0xffffffff);
  }

  else
  {
    set_err(EINVAL, "Unknown SNT device type '%s'", type);
    return 0;
  }

  // 'scsidev' is now owned by 'sntdev'
  scsidev_holder.release();
  return sntdev;
}
